A senior Labour politician has called on the Scottish National Party to explain what "devolution max" means.
Jim Murphy asked the question as the spotlight remained on SNP plans for a Scottish independence referendum.
Mr Murphy said phrases such as "devo max" and "indie lite" were lovely, but he did not know what they meant.
SNP leader Alex Salmond said a straight "yes" or "no" question would be on a referendum ballot but there could also be an option for full fiscal autonomy.
The first minister told the BBC's Andrew Marr show: "I am not for limiting choices of the Scottish people, I'll leave that to Westminster politicians."
He added: "I am confident we will win the referendum on Scottish independence."
However, Scottish MP and Shadow Defence Secretary Mr Murphy said it was time for the SNP to stop "shilly shallying" over the referendum date and "get on with it".
The SNP, which won the election in May, had said that an independence referendum would be held towards the latter part of its five-year parliamentary term.
'Best for Scotland'
In his interview with Andrew Marr, Mr Murphy said: "If you want to break up the UK, you have have to answer to some of the big questions about currency, about membership of the European Union and social security, pensions and so much else besides.
"What is best for Scotland is to remain in the UK."
Mr Salmond said that an independent Scotland would keep Sterling "until it was in Scotland's economic advantage to join the Euro and that would be the decision of the Scottish people".
He also made it clear that if independence was achieved then the country would have its own armed forces.
Members of the SNP, which won an overall majority at the election in May, have been meeting in Inverness at their annual conference.